SMOOTH task

This task convolves each channel map in a datacube with a given elliptical Gaussian.

Parameters

  • SMOOTH [false]. This flag enables the smooth algorithm. Can be true or false.

  • OBMAJ [none]. Major axis of the initial beam in arcsec. Do not set if you want to use the beam information in the input FITS file (the parameter overrides it).

  • OBMIN [none]. Minor axis of the initial beam in arcsec. Do not set if you want to use the beam information in the input FITS file (the parameter overrides it).

  • OBPA [none]. Position angle of the major axis of the initial beam in degrees. Do not set if you want to use the beam information in the input FITS file (the parameter overrides it).

  • BMAJ [none]. Major axis of the final beam in arcsec.

  • BMIN [none]. Minor axis of the final beam in arcsec.

  • BPA [none]. Position angle of the major axis of the final beam in degrees.

  • FACTOR [2]. If set, the beam of the output cube is [FACTOR*OBMAJ,FACTOR*OBMIN,OBPA]. Ignored if BMAJ, BMIN, BPA are specified.

  • SCALEFACTOR [none]. Scaling factor for output datacube. BBarolo will calculate an appropriate one if left unset.

  • FFT [true]. Whether to convolve by using Fast Fourier Transform or not.

  • REDUCE [false]. If true, BBarolo repixels the output datacube to preserve the number of pixels in a beam.

  • SMOOTHOUTPUT [none]. Output smoothed FITS file. Default is input file name with a suffix indicating the new beam size.

Outputs

The task writes the smoothed datacubes in the FITS file NAME_sN.fits, where NAME is the name of the galaxy and N is the new beam size.

Example

Below, an example parameter file to smooth the usual datacube to a coarser spatial resolution.

FITSFILE    ngc2403.fits
THREADS     4

/////////// SMOOTH parameters /////////////
SMOOTH      true
// New beam parameters.
BMAJ        150
BMIN        150     
BPA         0
// Repixeling
REDUCE      true
///////////////////////////////////////////


SMOOTHSPEC task

This task convolves each spectrum in a datacube with a given window, i.e. it performs spectral smoothing.

Parameters

  • SMOOTHSPEC [false]. This flag enables the spectral smoothing algorithm. Can be true or false.

  • WINDOW_TYPE [HANNING]. Type of the smoothing window. Implemented windows include HANNING, BOXCAR, BARTLETT, WELCH, BLACKMAN, FLATTOP.

  • WINDOW_SIZE [3]. Size of the smoothing window in channels.

  • REDUCE [false]. Whether to do channel resampling. If true, output data will be averaged over (WINDOW_SIZE+1)/2 channels.

Outputs

The task writes the smoothed datacube in the FITS file NAME_hN.fits, where NAME is the name of the galaxy and N is the size of the Hanning window.

Example

Below, a parameter file to Hanning smooth the usual datacube.

FITSFILE     ngc2403.fits

/////////// SPECSMOOTH parameters /////////////
SMOOTHSPEC   true
WINDOW_TYPE  HANNING
WINDOW_SIZE  11
///////////////////////////////////////////////